// Workers AI · dad joke modeWhy did Methapyrilene go to therapy? It had a meta problem.

"Thionylan" redirects here. Not to be confused with thionyl halides: thionyl fluoride, thionyl chloride and thionyl bromide.

Methapyrilene

Clinical data
ATC code	R06AC05 (WHO)
Identifiers
IUPAC name N,N-dimethyl-N'-pyridin-2-yl-N'-(2-thienylmethyl)ethane-1,2-diamine
CAS Number	91-80-5 Y
PubChem CID	4098
DrugBank	DB04819 Y
ChemSpider	3956 Y
UNII	A01LX40298
KEGG	C11114 Y
ChEBI	CHEBI:6820 Y
CompTox Dashboard (EPA)	DTXSID2023278
Chemical and physical data
Formula	C14H19N3S
Molar mass	261.39 g·mol−1
3D model (JSmol)	Interactive image
SMILES n1ccccc1N(CCN(C)C)Cc2sccc2
InChI InChI=1S/C14H19N3S/c1-16(2)9-10-17(12-13-6-5-11-18-13)14-7-3-4-8-15-14/h3-8,11H,9-10,12H2,1-2H3 Y Key:HNJJXZKZRAWDPF-UHFFFAOYSA-N Y
(verify)

Methapyrilene is an antihistamine and anticholinergic of the pyridine chemical class which was developed in the early 1950s. It was sold under the trade names Co-Pyronil and Histadyl EC in the UK. It has relatively strong sedative effects, to the extent that its primary use was as a medication for insomnia rather than for its antihistamine action. Together with scopolamine, it was the main ingredient in Sominex, Nytol, and Sleep-Eze. It also provided the sedative component of Excedrin PM. All of these products were reformulated in the late 1970s when methapyrilene was demonstrated to cause liver cancer in rats when given chronically.

See also

• Thenalidine
• Methaphenilene